NiO hollow microspheres interconnected by carbon nanotubes as an anode for lithium ion batteries

In this work, NiO hollow microspheres interconnected by multi-walled carbon nanotubes (MWCNTs) were prepared, characterized, and evaluated in terms of lithium ion storage properties. Characterization results showed that the NiO hollow microspheres were formed by self assembly of NiO nanoparticles promoted by MWCNTs, which connected the NiO microspheres to form a long-range network. Electrochemical measurement results showed a charge capacity as high as 597.2 mAh g when cycling at the rate 2 C and maintained 85.3% capacity of 0.1 C. After cycling for 100 times at 1 C, it maintained a capacity of 692.3 mAh g with retention 89.3% of the initial capacity. The observed excellent electrochemical performance is attributed to the presence of MWCNTs interconnecting the NiO microspheres of the composite material, of which electronic conductivity was improved, and the mesoporous hollow structure effectively alleviated the volume changes to maintain the structural stability during cycling

Empirical model for fitting the viscosity of lithium bromide solution with CuO nanoparticles and E414

To research viscosity fitting model of stable nano-lithium bromide solution (nano-LiBr), the stability of the nano-LiBr and the dynamic viscosity of LiBr were measued by Ultraviolet-visible spectroscopy (UV-vis) and rotational viscometer respectively. Two LiBr with different additives were measured, i.e., LiBr with dispersant (E414) and LiBr with dispersant + copper oxide nanoparticles (CuO). The ranges of measuring temperature were from 25°C–60°C, the concentrations of LiBr were from 50%–59%, the volume fractions of the dispersants were from 0%–4%, and the fractions of nanoparticle volume were from 0%–0.05%. Results indicated that the nano-LiBr with E414 had good stability. The viscosity of the LiBr decreased when temperature increased, and increased when LiBr concentration and dispersant amount were increased. It is also found that the viscosity was directly proportional to the volume fraction of the nanoparticles. This study also showed that the higher the concentration of the base fluid was, the more significant increase of the viscosity was. An empirical viscosity model of stable nano-LiBr with a maximum error of 13% was developed

The mechanism of high mobility group box-1 protein and its bidirectional regulation in tumors

High-mobility group box-1 protein (HMGB1) is a nonhistone chromatin-related protein widely found in eukaryotic cells. It is involved in the transcription, replication, and repair of DNA to maintain nuclear homeostasis. It participates in cell growth, differentiation, and signal transduction. Recent studies showed that HMGB1 has a bidirectional regulatory effect on tumors by regulating TLR4/MYD88/NF-κB and RAGE/AMPK/mTOR signaling pathways. On the one hand, it is highly expressed in a variety of tumors, promoting tumor proliferation and invasion, while on the other hand, it induces autophagy and apoptosis of tumor cells and stimulates tumor-infiltrating lymphocytes to produce an anti-tumor immune response. At present, HMGB1 could be used as a target to regulate the drug resistance and prognostication in cancer. Clinical applications of HMGB1 in cancer need further in-depth studies

From concept to action: a united, holistic and One Health approach to respond to the climate change crisis

It is unequivocal that human influence has warmed the planet, which is seriously affecting the planetary health including human health. Adapting climate change should not only be a slogan, but requires a united, holistic action and a paradigm shift from crisis response to an ambitious and integrated approach immediately. Recognizing the urgent needs to tackle the risk connection between climate change and One Health, the four key messages and recommendations that with the intent to guide further research and to promote international cooperation to achieve a more climate-resilient world are provided

A parametric study on natural frequency of sandwich panel using refined shear model

The natural frequency of a thick rectangular sandwich panel was studied using refined shear deformation theory. Both faces sheets and core materials are orthotropic. Nonlinear behavior of shear deformation of sandwich panel was described by a proposed polynomial function. The effect of transverse shear modulus of sandwich core on flexural vibration of the panel was investigated. Comparison was made among the classical thin plate theory, low order shear deformation theory and high order refined shear theory. Results from finite element analysis were also provided to verify the theoretical predictions

Natural Frequency Analysis of a Sandwich Panel with Soft Core Based on a Refined Shear Deformation Model

The natural frequency of a thick rectangular sandwich panel composed of orthotropic facesheets and a soft core was studied based on a refined shear deformation model. The shear deformation of the sandwich panel was described by a polynomial function. The effect of transverse shear modulus of the facesheets and core on flexural vibration of the panel was investigated. Comparison was made among classical thin plate theory, linear shear (low order) deformation theory and the refined shear (high order) deformation model. Results from finite element analysis were also provided to verify the theoretical predictions. It was shown that the refined shear deformation model provided a better prediction on the natural frequency of vibration of a sandwich panel than thin plate model or low order deformation model

Characterization of viscoelastic properties of polymer bar using iterative deconvolution in the time domain

A new approach to characterize the viscoelastic properties of a polymer bar using wave propagation phenomenon that is dominated by attenuation and dispersion is presented. A novel iterative deconvolution algorithm is proposed to directly extract the impulse response function (IRF) from the measured discrete strain signals in the time domain. The algorithm can identify the response of a linear time-invariant system from the measured input and output signals that are often subjected to noise and truncation. The derived IRF is the non-parametric characterization of the viscoelasticity of the polymer bar and is employed to predict strain signal at the next position and/or to retrieve strain signal at a previous position for verification. The parametric representation of the viscoelasticity is implemented on the basis of a universal linear viscoelastic (multiple Maxwell elements) model and the associated frequency response of the derived IRF. A spectrum of viscoelastic parameters was identified for the polymer bar and the results are presented. As an application example of this approach, a data reduction procedure to extract the high strain rate response of low impedance materials from strain signals obtained from a polymer split Hopkinson pressure bar is presented. © 2006 Elsevier Ltd. All rights reserved

Prediction of Natural Frequencies of a Sandwich Panel Using Thick Plate Theory

The vibration of a sandwich panel with two identical isotropic facesheets and an orthotropic core was studied. The governing partial differential equation was derived using a variational principle. Linear shear theory was employed to describe the transverse deformation of the panel, and the rotational effect was taken into consideration. The natural frequencies of a rectangular sandwich panel can be predicted on the basis of the proposed analytical model. Results from the proposed model were compared with those from thin plate theory. The effects of the structural and material parameters such as core anisotropy, core density, and facesheet thickness on natural frequencies were discussed. © 2001, Sage Publications. All rights reserved

Effect of Soft Honeycomb Core on Flexural Vibration of Sandwich Panel using Low Order and High Order Shear Deformation Models

Low order and high order shear deformation models are applied to investigate the effect of honeycomb core (transversely shear deformable) on flexural vibration of thick rectangular sandwich panel with isotropic facesheets. Strain and kinetic energy of sandwich panel are expressed in terms of material properties and structural parameters. Partial differential equations are derived based upon a variational principle. Solutions in Navier form are obtained for a simply supported rectangular panel. The effect of honeycomb core parameters, such as characteristic angle, cell wall thickness, and cell size is studied. Comparison between low order model, high order model, and finite element method is provided. It is shown that in most cases results from a high order model without facesheet shear effect are close to those from finite element analysis

Behavior Pattern and Parametric Characterization for Low Density Crushable Foams

Crushable foams may be used for shock mitigation and impact absorption applications that take advantage of their complex compression behavior. It is highly desirable that their constitutive behavior be characterized by suitable models with meaningful parameters such as Young\u27s modulus for linear elasticity. This work describes constitutive behavior patterns and parametric characterization for low density crushable foams. Compression tests under large deformation were conducted on polyurethane foams of different densities. Various behavior patterns were observed that differ from the well-known three-stage behavior for porous materials. A set of multi-parameter models was proposed to parametrically characterize the behavior patterns. The constitutive model was intended to serve as a framework for crushability characterization